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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Copyright 2007 the original author or authors.<a name="line.2"></a>
<FONT color="green">003</FONT>     *<a name="line.3"></a>
<FONT color="green">004</FONT>     * Licensed under the Apache License, Version 2.0 (the "License");<a name="line.4"></a>
<FONT color="green">005</FONT>     * you may not use this file except in compliance with the License.<a name="line.5"></a>
<FONT color="green">006</FONT>     * You may obtain a copy of the License at<a name="line.6"></a>
<FONT color="green">007</FONT>     *<a name="line.7"></a>
<FONT color="green">008</FONT>     *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.8"></a>
<FONT color="green">009</FONT>     *<a name="line.9"></a>
<FONT color="green">010</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.10"></a>
<FONT color="green">011</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.11"></a>
<FONT color="green">012</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.12"></a>
<FONT color="green">013</FONT>     * See the License for the specific language governing permissions and<a name="line.13"></a>
<FONT color="green">014</FONT>     * limitations under the License.<a name="line.14"></a>
<FONT color="green">015</FONT>     */<a name="line.15"></a>
<FONT color="green">016</FONT>    package org.codehaus.groovy.grails.plugins.searchable.util;<a name="line.16"></a>
<FONT color="green">017</FONT>    <a name="line.17"></a>
<FONT color="green">018</FONT>    import org.apache.lucene.index.Term;<a name="line.18"></a>
<FONT color="green">019</FONT>    import org.apache.lucene.analysis.WhitespaceAnalyzer;<a name="line.19"></a>
<FONT color="green">020</FONT>    import org.apache.lucene.analysis.SimpleAnalyzer;<a name="line.20"></a>
<FONT color="green">021</FONT>    import org.apache.lucene.queryParser.ParseException;<a name="line.21"></a>
<FONT color="green">022</FONT>    import org.apache.commons.logging.Log;<a name="line.22"></a>
<FONT color="green">023</FONT>    import org.apache.commons.logging.LogFactory;<a name="line.23"></a>
<FONT color="green">024</FONT>    import org.codehaus.groovy.grails.plugins.searchable.lucene.LuceneUtils;<a name="line.24"></a>
<FONT color="green">025</FONT>    <a name="line.25"></a>
<FONT color="green">026</FONT>    import java.text.MessageFormat;<a name="line.26"></a>
<FONT color="green">027</FONT>    <a name="line.27"></a>
<FONT color="green">028</FONT>    /**<a name="line.28"></a>
<FONT color="green">029</FONT>     * @author Maurice Nicholson<a name="line.29"></a>
<FONT color="green">030</FONT>     */<a name="line.30"></a>
<FONT color="green">031</FONT>    public class StringQueryUtils {<a name="line.31"></a>
<FONT color="green">032</FONT>        private static final Log LOG = LogFactory.getLog(StringQueryUtils.class);<a name="line.32"></a>
<FONT color="green">033</FONT>    <a name="line.33"></a>
<FONT color="green">034</FONT>        /** The default highlight pattern */<a name="line.34"></a>
<FONT color="green">035</FONT>        public static final String DEFAULT_DIFFS_HIGHLIGHT_PATTERN = "&lt;b&gt;&lt;i&gt;{0}&lt;/i&gt;&lt;/b&gt;";<a name="line.35"></a>
<FONT color="green">036</FONT>    <a name="line.36"></a>
<FONT color="green">037</FONT>        /**<a name="line.37"></a>
<FONT color="green">038</FONT>         * Highlights the different terms in the second query and returns a new query string.<a name="line.38"></a>
<FONT color="green">039</FONT>         * Diffs are highlighted using {@link #DEFAULT_DIFFS_HIGHLIGHT_PATTERN}; for alternative<a name="line.39"></a>
<FONT color="green">040</FONT>         * formats use {@link #highlightTermDiffs(String, String, String)}.<a name="line.40"></a>
<FONT color="green">041</FONT>         * This method is intended to be used with suggested queries to display the suggestion<a name="line.41"></a>
<FONT color="green">042</FONT>         * to the user in highlighted format, as per Google, so the queries are expected to roughly match<a name="line.42"></a>
<FONT color="green">043</FONT>         * @param first the original query<a name="line.43"></a>
<FONT color="green">044</FONT>         * @param second the second query, in which to highlight differences<a name="line.44"></a>
<FONT color="green">045</FONT>         * zero is the highlighted term text<a name="line.45"></a>
<FONT color="green">046</FONT>         * @return a new copy of second with term differences highlighted<a name="line.46"></a>
<FONT color="green">047</FONT>         * @throws ParseException if either first or second query is invalid<a name="line.47"></a>
<FONT color="green">048</FONT>         * @see #highlightTermDiffs(String, String, String)<a name="line.48"></a>
<FONT color="green">049</FONT>         */<a name="line.49"></a>
<FONT color="green">050</FONT>        public static String highlightTermDiffs(String first, String second) throws ParseException {<a name="line.50"></a>
<FONT color="green">051</FONT>            return highlightTermDiffs(first, second, DEFAULT_DIFFS_HIGHLIGHT_PATTERN);<a name="line.51"></a>
<FONT color="green">052</FONT>        }<a name="line.52"></a>
<FONT color="green">053</FONT>    <a name="line.53"></a>
<FONT color="green">054</FONT>        /**<a name="line.54"></a>
<FONT color="green">055</FONT>         * Highlights the different terms in the second query and returns a new query string.<a name="line.55"></a>
<FONT color="green">056</FONT>         * This method is intended to be used with suggested queries to display the suggestion<a name="line.56"></a>
<FONT color="green">057</FONT>         * to the user in highlighted format, as per Google, so the queries are expected to roughly match<a name="line.57"></a>
<FONT color="green">058</FONT>         * @param first the original query<a name="line.58"></a>
<FONT color="green">059</FONT>         * @param second the second query, in which to highlight differences<a name="line.59"></a>
<FONT color="green">060</FONT>         * @param highlightPattern the pattern used to highlight; should be a {@link MessageFormat} pattern where argument<a name="line.60"></a>
<FONT color="green">061</FONT>         * zero is the highlighted term text<a name="line.61"></a>
<FONT color="green">062</FONT>         * @return a new copy of second with term differences highlighted<a name="line.62"></a>
<FONT color="green">063</FONT>         * @throws ParseException if either first or second query is invalid<a name="line.63"></a>
<FONT color="green">064</FONT>         * @see #highlightTermDiffs(String, String)<a name="line.64"></a>
<FONT color="green">065</FONT>         */<a name="line.65"></a>
<FONT color="green">066</FONT>        public static String highlightTermDiffs(String first, String second, String highlightPattern) throws ParseException {<a name="line.66"></a>
<FONT color="green">067</FONT>            final String defaultField = "$StringQueryUtils_highlightTermDiffs$";<a name="line.67"></a>
<FONT color="green">068</FONT>            Term[] firstTerms = LuceneUtils.realTermsForQueryString(defaultField, first, WhitespaceAnalyzer.class);<a name="line.68"></a>
<FONT color="green">069</FONT>            Term[] secondTerms = LuceneUtils.realTermsForQueryString(defaultField, second, WhitespaceAnalyzer.class);<a name="line.69"></a>
<FONT color="green">070</FONT>    <a name="line.70"></a>
<FONT color="green">071</FONT>            if (firstTerms.length != secondTerms.length) {<a name="line.71"></a>
<FONT color="green">072</FONT>                LOG.warn(<a name="line.72"></a>
<FONT color="green">073</FONT>                    "Expected the same number of terms for first query [" + first + "] and second query [" + second + "], " +<a name="line.73"></a>
<FONT color="green">074</FONT>                    "but first query has [" + firstTerms.length + "] terms and second query has [" + secondTerms.length + "] terms " +<a name="line.74"></a>
<FONT color="green">075</FONT>                    "so unable to provide user friendly version. Returning second query as-is."<a name="line.75"></a>
<FONT color="green">076</FONT>                );<a name="line.76"></a>
<FONT color="green">077</FONT>                return second;<a name="line.77"></a>
<FONT color="green">078</FONT>            }<a name="line.78"></a>
<FONT color="green">079</FONT>    <a name="line.79"></a>
<FONT color="green">080</FONT>            MessageFormat format = new MessageFormat(highlightPattern);<a name="line.80"></a>
<FONT color="green">081</FONT>            StringBuffer diff = new StringBuffer(second);<a name="line.81"></a>
<FONT color="green">082</FONT>            int offset = 0;<a name="line.82"></a>
<FONT color="green">083</FONT>            for (int i = 0; i &lt; secondTerms.length; i++) {<a name="line.83"></a>
<FONT color="green">084</FONT>                Term firstTerm = firstTerms[i];<a name="line.84"></a>
<FONT color="green">085</FONT>                Term secondTerm = secondTerms[i];<a name="line.85"></a>
<FONT color="green">086</FONT>                boolean noField = defaultField.equals(secondTerm.field());<a name="line.86"></a>
<FONT color="green">087</FONT>                String snippet = noField ? secondTerm.text() : secondTerm.field() + ":" + secondTerm.text();<a name="line.87"></a>
<FONT color="green">088</FONT>                int pos = diff.indexOf(snippet, offset);<a name="line.88"></a>
<FONT color="green">089</FONT>                if (!firstTerm.text().equals(secondTerm.text())) {<a name="line.89"></a>
<FONT color="green">090</FONT>                    if (!noField) {<a name="line.90"></a>
<FONT color="green">091</FONT>                        pos += secondTerm.field().length() + 1;<a name="line.91"></a>
<FONT color="green">092</FONT>                    }<a name="line.92"></a>
<FONT color="green">093</FONT>                    diff.replace(pos, pos + secondTerm.text().length(), format.format(new Object[] { secondTerm.text() }));<a name="line.93"></a>
<FONT color="green">094</FONT>                }<a name="line.94"></a>
<FONT color="green">095</FONT>                offset = pos;<a name="line.95"></a>
<FONT color="green">096</FONT>            }<a name="line.96"></a>
<FONT color="green">097</FONT>            return diff.toString();<a name="line.97"></a>
<FONT color="green">098</FONT>        }<a name="line.98"></a>
<FONT color="green">099</FONT>    }<a name="line.99"></a>




























































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